This invention relates to the field of computerized navigation systems, and in particular, to such systems equipped with a database of image data in addition to the standard routing and directional data.
Computerized navigation systems are now available which enable a traveler to follow a customized route to his destination, without the use of conventional directions or printed maps. As these systems become more widely available, there will be an increasing need to make them easier to understand and to operate.
In this regard, it may be easier for some people to remember landmarks than the details of a printed map. People can become lost despite being given both a reasonable map and written directions on how to follow it. In comparison, directions that use objects in the environment that we are likely to notice are more easily followed; for example, "You'll drive for a couple of miles and then pass a bright red farmhouse all by itself; take the first left after that." Such instructions may be much easier to remember.
Accordingly, the ease of use of computerized navigation systems would be greatly enhanced if pictorial cues to the geographic data could be provided along with the navigation directions. Specifically, the directions provided by such systems would be easier to follow if the user could see a display of photographs of the actual locations along the route, in addition to the route being displayed in a text or map format.
In general, presently available enhancements to computerized navigation systems aim to convey additional information which a driver may use to streamline the navigation process. For example, some Japanese systems transmit data about accidents, traffic congestion, availability of parking, road construction, and other specialized data to in-vehicle navigation devices. Such a navigation system may take these data into account when planning routes. In addition, earlier work on synthesized speech and voice-control systems is being incorporated into in-vehicle navigation systems so that drivers need not take their eyes off the road to interact with the system, as reported in Global Positioning & Navigation News.
In one particular application of computerized navigation, systems incorporating Global Positioning System (GPS) receivers are installed in motor vehicles. Some GPS units, such as the GPS 4000, allow the user to define custom landmarks ("the old oak tree," "my favorite fishing hole"). These landmarks are shown on the unit's readout whenever the user approaches them.
Amtrak offers an on-line national map that describes every Amtrak route, scenery along the way, amenities, and seating and sleeping car accommodations. This is not useful to automotive and other travelers not using common carriers who need directions.
There are a number of maps, both print and computerized, that incorporate business logos. Various cities around the world have tourist-oriented maps that incorporate subject headings (restaurants, hotels, attractions) with logos of relevant businesses into a single interactive web-based map. Various web sites offer point-to-point driving directions between street addresses and/or cities in the United States, Canada, and occasionally, certain cities on other continents. In some instances, corporate logos are superimposed on maps as a way to identify features of interest to the traveler.
There are various single-user CD-ROM-based navigational products which may optionally be interfaced with portable GPS receivers to provide a real-time superimposition of the GPS location on the digital map. These products may include a variety of multimedia data, e.g. for users who specify San Francisco as their destination, the product might show a photograph of the Golden Gate Bridge. The location in the photograph may or may not be a useful landmark for a traveler following a customized route.
Several websites provide customized maps and driving directions. Several CD-ROMS, such as Travroute Software's Door-to-Door, also provide this service. MapQuest's maps have a feature called "points of interest" that lets the user choose a set of landmarks to be added to a custom map. For example, one could choose to display all the restaurants near one's destination; these would show up on the map as generic icons (such as a crossed knife and fork) and names. MapQuest also allows companies to pay to have their corporate logo displayed on the map, instead of a generic icon. However, these logos only appear on MapQuest's maps, and do not accompany driving directions. Travroute's Door-to-Door CD-ROM and the Freetrip website have similar features.
Northern Illinois University provides a campus tour planner on its website, including a clickable campus map with numbers indicating landmarks. Clicking on one of the numbers results in a display of a picture and description of the landmark. This may be viewed as a very small database of photographs for use in navigation. However, this system does not assemble the photographs into a set of customized directions for getting from one point to another.
Databases of photographs have been used in navigation for robots. One solution to the problem of getting a robot from one point to another is to have it store images of various points along its route, then retrace the route by matching what it sees with images in its database. This system does not, of course, create directions or maps that would be useful to a human.
"Database Requirements for Vehicle Navigation Systems," published by the National Center for Geographic Information and Analysis (NCGIA) at the University of Maine, describes different data types and properties necessary for the system to associate adjacent spaces together in an effort to plan a multi-step route. This paper also notes that the U.S. Census Bureau's TIGER (Topologically Integrated Geographic Encoding and Referencing) files, which provide sufficient detail for accurate vehicle navigation, occupy approximately 3,600 megabytes of storage. These files specify the geometry of roads, geographic attribute data, and additional features such as county boundaries.
U.S. Pat. No. 5,329,108, entitled "Map with indexes for a geographical information system and system for applying same," describes a method of applying index data to the printed surface of a geographical map; the index data represents information necessary to reproduce the contents of a region of an analog printed map with which the index data is associated.
U.S. Pat. No. 5,528,518, entitled "System and method for collecting data used to form a geographic information system database," describes a portable data-acquisition device which combines a GPS receiver and a means of collecting information about objects viewable from the reference location established by the device's absolute geographical location. The device may thus collect location information that describes geography both in terms of its absolute coordinates as determined by the GPS, and with reference to notable objects near each GPS reference point.
U.S. Pat. No. 5,648,768, entitled "System and method for identifying, tabulating and presenting information of interest along a travel route," describes a database system for entering starting and destination points, retrieving route information, and presenting the route information alongside other data relevant to the route.
U.S. Pat. No. 5,614,898, entitled "Guide system," describes a system for providing supplemental information to users present in a tour bus or similar large-capacity passenger vehicle. If, for example, the bus drives near a famous building, the guide might provide basic information about the landmark, and the system might retrieve extensive historical data and present it in the form of a multimedia show.
U.S. Pat. No. 5,596,494, entitled "Method and apparatus for acquiring digital maps," describes a method for acquiring airborne stereoscopic images from satellites and correlating them with GPS coordinates in a three-dimensional space. It is subsequently possible to provide a display of actual location on real photographic maps, rather than approximated digital representations thereof. A plurality of possible GPS coordinates are thus associated with a single visual image. The satellite photographs used in this system are very large-scale and do not offer visual representations of landmarks along an individual traveler's route.
U.S. Pat. No. 5,587,911, entitled "Navigation system with selective intersection display," describes a new database format to be used for storing the data traditionally used by navigation systems. In its detailed specification, it describes an external memory "in which is stored all the data necessary for the route guidance including data for maps . . . branching points, photographs, destinations . . . and speech guidance."
U.S. Pat. No. 5,537,323, entitled "Navigation device vehicle comprising the device," describes a navigation system having a map display unit updated in accordance with changes in the user's position.
U.S. Pat. No. 5,442,557, entitled "Navigation device," describes an in-car navigation system, featuring a database of "conspicuous objects" to be consulted when assembling routing information for a given origin/destination pair. However, this patent does not mention a database including photographs of all incidental intersections or general-purpose buildings that a user might witness during the navigation process.